yashsingh1/xdaforums huggingface dataset:
[Nook Color General] mrkkk:
Here are my results

sandisk 8gb sdhc

and patriot 16gb

:D

bought the sandisk cards from ebay, from rswireless10

==

sandisk numbers, swoozle please update your first post, thanks

Sequential Read : 18.11 MB/s
Sequential Write : 6.127 MB/s
Random Read 512KB : 17.72 MB/s
Random Write 512KB : 1.622 MB/s
Random Read 4KB (QD=1) : 3.392 MB/s
Random Write 4KB (QD=1) : 1.315 MB/s
Random Read 4KB (QD=32) : 3.111 MB/s
Random Write 4KB (QD=32) : 1.208 MB/s

Test : 50 MB [G: 0.0% (8 GB)]
Date : 2011/07/28
OS : Windows 7 SP1
[Nook Color General] mrkkk:
something wrong here

that image file is old

:D

see this http://mrm3.net/nook-color-honeycomb-3-0-guide/

http://xdaforums.com/showthread.php?t=1074471
[Nook Color General] stolenmoment:
The /sdcard and /emmc partitions are FAT32 filesystems (that's why Windoze PCs can use them); Android uses ext for the others, which have less churn.
[Nook Color General] caspermi:
I wanted to install CM7 on my wife's Nook and preferred the SD boot option. I did my homework and read all these posts where Sandisk micro SD's were recommended. Went to Microcenter and picked up a Sandisk 4G class 4 card. I must have tried ten times and could not install CM7 successfully as the Nook would not boot.

I finally went to test my card using CrystalDiskMark 3.0.1 and these are the results:

Sequential Read : 9.215 MB/s

Sequential Write : 6.715 MB/s

Random Read 512KB : 9.034 MB/s

Random Write 512KB : 0.063 MB/s

Random Read 4KB (QD=1) : 1.984 MB/s

Random Write 4KB (QD=1) : 0.009 MB/s

Random Read 4KB (QD=32) : 2.022 MB/s

Random Write 4KB (QD=32) : 0.009 MB/s

Test : 50 MB [G: 0.0% (0.0/3922 MB)] (x5)

What surprised me were the poor write speeds with this Sandisk 4G class 4 card.

I haven't seen anyone post write speeds for a Sandisk card that were this low. Was this card from a bad batch or some other issue? I'll be out shopping for new card tomorrow.
[Nook Color General] Dudemeister:
Here is what my CM7 SD card looks like:

Partition 1 - FAT32 - 5.89GB. THis is the partition where all the data is usually installed, movies, books, music, downloads, and where (some) apps can be moved to.

Partition 2 - ext3 - 965MB. This is where all the apps get installed to by default.

Partition 3 - ext3 - 463MB. This is where CM7, and all its parts and bits reside.

Partition 4 - FAT32 - 118MB. This contains the recovery engine

It's that ext3 partition that the OS is loaded on, and gets most of the workout.

The large FAT32 partition where all the media goes on, usually gets mostly read from, but not written to. THis partition is considered the "SD card"

Most apps when installed go into Partition 2. The reason this partition is there, and is ext3 is because some apps, especially widgets, must be available during boot. FAT32 partitions like the "SD card" partition are mounted

after

the system is completely loaded, and the apps would not be available during boot if they were on it.

AS you can see, the most important and the most used partitions are the ext3 partitions. The FAT32, not so much.
[Nook Color General] Dashie84:
Sandisk 16gb SDSDQM-016G-B35

-----------------------------------------------------------------------

CrystalDiskMark 3.0.1 x64 (C) 2007-2010 hiyohiyo

Crystal Dew World : http://crystalmark.info/

-----------------------------------------------------------------------

* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]

Sequential Read : 12.046 MB/s

Sequential Write : 6.210 MB/s

Random Read 512KB : 11.843 MB/s

Random Write 512KB : 2.520 MB/s

Random Read 4KB (QD=1) : 3.474 MB/s [ 848.1 IOPS]

Random Write 4KB (QD=1) : 0.522 MB/s [ 127.4 IOPS]

Random Read 4KB (QD=32) : 3.574 MB/s [ 872.6 IOPS]

Random Write 4KB (QD=32) : 0.519 MB/s [ 126.6 IOPS]

Test : 50 MB [E: 0.0% (0.0/14.8 GB)] (x5)

Date : 2011/08/02 13:00:51

OS : Windows 7 Ultimate Edition SP1 [6.1 Build 7601] (x64)

Random Write seem very poor compared to the 1.5mb/s standard of the thread, i have a faulty one and suggest me to change?
[Nook Color General] lexxon87:
Hey all,

I don't have read/write numbers for you, but I'd just like to mention that I used a Class 4 SanDisk 32GB (it actually came with my Thunderbolt) for CM7 for a coworker's daughter who thought she would need the storage for videos and such. It seems to run as well as it did on the 8GB, although I didn't get a lot of time with it. Certainly no immediate slowdown or FC issues, though.
[Nook Color General] Dashie84:
I changed the card. here the result

-----------------------------------------------------------------------

CrystalDiskMark 3.0.1 x64 (C) 2007-2010 hiyohiyo

Crystal Dew World : http://crystalmark.info/

-----------------------------------------------------------------------

* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]

Sequential Read : 12.048 MB/s

Sequential Write : 6.116 MB/s

Random Read 512KB : 11.846 MB/s

Random Write 512KB : 2.070 MB/s

Random Read 4KB (QD=1) : 3.490 MB/s [ 852.1 IOPS]

Random Write 4KB (QD=1) : 0.557 MB/s [ 136.0 IOPS]

Random Read 4KB (QD=32) : 3.628 MB/s [ 885.7 IOPS]

Random Write 4KB (QD=32) : 0.591 MB/s [ 144.2 IOPS]

Test : 50 MB [E: 0.0% (0.0/14.8 GB)] (x5)

Date : 2011/08/02 14:55:15

OS : Windows 7 Ultimate Edition SP1 [6.1 Build 7601] (x64)

Probabily i have choose the wrong shop asdasd
[Nook Color General] JoMama!:
Possible Fix for slow SD card

I think I may have a fix for the sd card slowness some of us are experiencing...

I've been frustrated by the random slowness and intermittent wireless issues on my 8Gb Patriot (class 4) and a Kingston 16GB card.

Recently I decided to try changing the block size of the second file system on the card and preliminarily I have pretty good results.

Last night I plugged the sd card into my Linux laptop. The system recognized and mounted four file systems

(/boot, an ext4 linux file sys with 1k blocksize, an ext4 linux file system with 4k block size, and the final ms-dos file system.)

I backed up the second file system with tar, unmounted it, then executed a mke2fs -b 1024 to get rid of the 4k block size and ran an i/o benchmark called bonnie++.

I did this about 40 times, alternating the block size between 1k, 2k and 4k.

In all tests, I consistently noticed improved throughput with 1k blocks - it was about 3-4x better on small writes (as compared to a 4k blocks.)

I also observed that (only on the 4k filesystem) my linux box consumed a lot of CPU as the benchmarrk filled the file system (df approached >70% full.)

Today I recovered the previous filesystem after changing it's block size to 1k and reinserted / restarted.

To my very pleasant surprise, CM7 on the nook is as Zippy and the browser is close to the "feel" of the non-rooted nook.

I will continue to test and experiment, but I wanted to see if anyone else might attempt this to duplicate & validate.

My theory is that the small block random reads / writes are improved dramatically, and that the journaling causes extra overhead (CPU consumption) at highed percentages of file system utilization.

Anybody want to give it a try and report back ??
[Nook Color General] Blue6IX:
I like this thought and approach, it makes sense.

Unfortunately I only have a windows xp box available to me - which I know cripples my ability to do stuff like this...if it's even possible it's a million times more complicated with windows then with linux.

Wouldn't trade though, linux and android run nice, windows runs like ...well, less nice we will say.

Is there any way I can complete the same operation on a windows box, or does it have to be done in linux?

Unfortunately at this time the only computer I have is the one i've been doing the testing on, and installing linux on it is not possible, even in a dual boot scenario.

I don't want to push the thread off-topic for gathering memory card results, but this may be one more piece of the smooth-running puzzle.

It's also likely that this could make some of these other non-SanDisk MicroSD cards perform better - which would make a whole lot of people happy.

Looking forward to more info on this, and still looking forward to people's memory card results. The 32 gig cards are slowly filtering in more, and this thread has been a fantastic eye opener for a lot of people.
[Nook Color General] Nick N:
I am preparing a MicroSD card with CM7 for the Nook Color being delivered today, decided to test out a few cards I have lying around:

Patriot 4GB Class 10 MicroSDHC

Sequential Read : 17.990 MB/s

Sequential Write : 6.582 MB/s

Random Read 4KB (QD=32) : 3.485 MB/s

Random Write 4KB (QD=32) : 0.018 MB/s

Test : 50 MB [E: 0.0% (0.0/3804.6 MB)] (x5) <All 0x00, 0Fill>

Kingston 4GB Class 4 MicroSDHC

Sequential Read : 15.749 MB/s

Sequential Write : 6.257 MB/s

Random Read 4KB (QD=32) : 4.012 MB/s

Random Write 4KB (QD=32) : 0.022 MB/s

Test : 50 MB [E: 0.0% (0.0/3774.0 MB)] (x5) <All 0x00, 0Fill>

Samsung 8GB Class 2 MicroSDHC (Included with HTC Evo)

Sequential Read : 11.292 MB/s

Sequential Write : 5.372 MB/s

Random Read 4KB (QD=32) : 2.608 MB/s

Random Write 4KB (QD=32) : 0.010 MB/s

Test : 50 MB [E: 0.0% (0.0/7672.0 MB)] (x5) <All 0x00, 0Fill>
[Nook Color General] Dudemeister:
In Windows XP or 7? not really, there are some utilities that will let you look at theses partitions, but not modify them.

But there is an option. You can download a Linux

Live

disc (CD or USB drive), boot from it, and work with your SD card, without having to physically install Linux on your machine.
[Nook Color General] Nick N:
I had to do the same thing when I formatted my hard drive to ext3 for my Tomato Router.
[Nook Color General] Curley_Joe:
I couldn't get CrystalDiskMark 3 to run correctly on my system, so I used the "winsat" command built in to Windows 7 to test two SanDisk cards I bought recently from NewEgg.

Commands:

winsat disk -ran -iocount 20 -drive Z -ransize 4096 -read

winsat disk -ran -iocount 20 -drive Z -ransize 4096 -write

Card 1:

SanDisk C2 8GB - model number SDSDQ-8192-A11M

NewEgg item number: N82E16820171363

Random 4K read: 3.16 MB/s

Random 4K write: 0.01 MB/s

Card 2:

SanDisk C4 16GB - model number SDSDQM-016G-B35N

NewEgg item number: N82E16820171486

Random 4K read: 2.10 MB/s

Random 4K write: 1.22 MB/s
[Nook Color General] fanoush:
Very interesting results. The most interesting is that according to things currently known it should not be like that so possibly this may be some side effect of going from very sub-optimal state to another sub-optimal state which performs better :-)

Some (very?) technical info:

wiki.linaro.org/WorkingGroups/KernelConsolidation/Projects/FlashCardSurvey

lwn.net/Articles/428584/

(sorry I cannot post direct links yet, as a new user I would need to spam you with 7 posts first to be allowed to enter direct links :-)

What I understood from that is that most critical is partition alignment and writing in bigger blocks. And of course cheap cards are really unusable for anything but sequential writes.

I run CM7 from SD card using verygreen's "[v1.3] Size-agnostic SD Card image and CM7 installer for SD Cards" and can confirm the partitions are definitely not aligned properly (at 4MB boundaries) and start at odd sectors.

Unfortunately the first partition must be currently unaligned due to MLO loader (a.k.a. X-loader) expecting old DOS layout with 63 sectors per cylinder. At least it did not boot for me when first partition start at block 8192 (as most cards come preformatted). Looks like there is a fix

comments.gmane.org/gmane.comp.embedded.pandaboard/2104 but most probably it is not compiled in current nook version of x-loader. But anyway even if first partition is misaligned it should be possible to align at least next partitions and hopefully everything will be faster even with default 4KB blocks and using 1KB blocks may become slower then.

I had no time so far to re-align partitions or modify vg's installer to create better aligned partitions so all this is just a theory. But if you went that far maybe you have skills/time/motivation to try it too?

I only tried to write vg's installer to card, then realign first partition to sector 8192 before booting it for the first time (hoping the installer will align also next partitions) and it did not boot at all most probaly due to MLO limitation mentioned above. I plan to try re-align at least next partitions of already installed system (First by inserting holes between partitions, shriking last FAT32 partition and dd-ing android system and data ext4 partitions. And then maybe by resizing or reformatting them and filesystem level) but maybe you'll be faster than me?
[Nook Color General] fanoush:
Just correcting myself on this. At least in the B&N published source of x-loader

at images.barnesandnoble.com/PResources/download/Nook/source-code/nookcolor-source-code.zip the start of first partition is not hardcoded to sector 63 so I am not sure why the vg's installer did not boot for me when re-aligning first partition. will try again.

Regardless of this, it would be great if anyone who cares could try to re-align CM7 partitions to 4MB boundary and check the speed difference.

BTW, Here is output of fdisk listing of partition table on 8GB card prepared with verygreen's SD installer (fdisk display units are set to sector)

Disk /dev/sdb: 8166 MB, 8166309888 bytes
255 heads, 63 sectors/track, 992 cylinders, total 15949824 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x5387f638

Device Boot Start End Blocks Id System
/dev/sdb1 * 63 240974 120456 c W95 FAT32 (LBA)
/dev/sdb2 240975 1188809 473917+ 83 Linux
/dev/sdb3 1188810 3164804 987997+ 83 Linux
/dev/sdb4 3164805 15936479 6385837+ c W95 FAT32 (LBA)

It could be seen that the partitions are aligned to cylinders (of 16065 * 512 = 8225280 bytes) so all but third partition does not even start on 1KB boundary!!! , not talking about ideal 4MB boundary :-)

But if JoMama! benchmarked second linux partition = the third one (=android user data partition not system one, system is read only anyway, the data one is regularly written into) which is 1024 bytes aligned, it may somehow explain the speedup with 1KB blocks since at least 1KB blocks do not go against internal card layout (i.e they fit into some single NAND page even if pages are much bigger) but 4KB block writes may cross internal page boundaries (or even sometimes eraseblock or AU boudaries) so it may cause more work for the card.
[Nook Color General] Curley_Joe:
I am also running CM7 from an sdcard using verygreen's installer.

It seems as though the boot partition can be moved, as long as the start and end sectors are aligned to the start and end of a cylinder. If the start sector is not aligned to a cylinder, I get no boot. On the other hand, if the start sector is aligned but the end sector is not, it boots into the stock B&N ROM.

I think the thing to do is to ask verygreen to update his generic-sdcard image so that non-boot partitions are aligned at 4K offsets. Just now I attampted to send him a private message about this. If that doesn't work we can try posting a message in his "Size-agnostic ..." thread.
[Nook Color General] fanoush:
If it boots to stock B&N then the small OMAP CPU boot ROM decides the card is not bootable and boots internal mmc instead. This ROM is burned into CPU so nothing can be done about its limitations. If it hangs, it means CPU boot ROM decides there is MLO on the card and runs it. Then MLO tries to load u-boot.bin, u-boot tries to load linux kernel, ramdisk etc. Any part in this chain (well, except linux kernel which is IMO the most robust part) may have hardcoded expectation about partition layout and fail, i.e. MLO or u-boot may have the issue or vg's custom partitioning code in ramdisk can rely on known format of its own image.

Yes, thought about this too but first I wanted to have some results.

One issue that affects runtime performance is android system and user data partition alignment. Another is 4th FAT partition used when installing android stuff to card or when USB storage is enabled. I see quite poor performance when transferring media (movies) over usb cable, this is linear writing that any cheap card should handle pretty fast so the slowdown is likely due to misaligned partition layout.

Also the technical info says some cheap cards expect FAT table to be somewhere near the beginning of the card and handle those blocks differently so maybe the most optimal for fast usb storage transfers is to keep first partition as the only big FAT partition and keep both boot files and media there. This can get messy and dangerous though.
[Nook Color General] Curley_Joe:
Hmm. Using winsat, I'm not seeing any significant speed difference between FAT32 file systems aligned at cylinders vs. 4K boundaries. (I'm testing random access and sequential access of 4k blocks on three different sdhc cards.)

While benchmarks on Windows and Linux are useful, it would be best if we could find a benchmarking program that runs under Android.
[Nook Color General] m8cca:
Transcend 32gb CL4 CrystalMark results

Didn't find detail on this card in thread yet.

Results from the Transcend 32gb CL4 card I just got:

-----------------------------------------------------------------------

CrystalDiskMark 3.0.1 (C) 2007-2010 hiyohiyo

Crystal Dew World : http://crystalmark.info/

-----------------------------------------------------------------------

* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]

Sequential Read : 20.106 MB/s

Sequential Write : 4.900 MB/s

Random Read 512KB : 19.439 MB/s

Random Write 512KB : 1.461 MB/s

Random Read 4KB (QD=1) : 2.844 MB/s [ 694.3 IOPS]

Random Write 4KB (QD=1) : 1.060 MB/s [ 258.8 IOPS]

Random Read 4KB (QD=32) : 3.196 MB/s [ 780.3 IOPS]

Random Write 4KB (QD=32) : 1.021 MB/s [ 249.2 IOPS]

Test : 50 MB [H: 0.0% (0.0/29.7 GB)] (x9)

Date : 2011/08/29 23:53:58

OS : Windows Server 2003 Enterprise Edition SP2 [5.2 Build 3790] (x86)

Transcend 32gb Class 4
[Nook Color General] KidJoe:
Sandisk 32gig CL4 SDSDQ-032G-A11M

-----------------------------------------------------------------------

CrystalDiskMark 3.0.1 x64 (C) 2007-2010 hiyohiyo

Crystal Dew World : http://crystalmark.info/

-----------------------------------------------------------------------

* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]

Sequential Read : 20.910 MB/s

Sequential Write : 5.073 MB/s

Random Read 512KB : 20.230 MB/s

Random Write 512KB : 1.506 MB/s

Random Read 4KB (QD=1) : 3.119 MB/s [ 761.5 IOPS]

Random Write 4KB (QD=1) : 1.020 MB/s [ 249.0 IOPS]

Random Read 4KB (QD=32) : 3.290 MB/s [ 803.2 IOPS]

Random Write 4KB (QD=32) : 0.955 MB/s [ 233.2 IOPS]

Test : 50 MB [N: 0.0% (0.0/29.7 GB)] (x5)

Date : 2011/09/09 19:56:37

OS : Windows 7 Ultimate Edition SP1 [6.1 Build 7601] (x64)
[Nook Color General] w0mbl3:
Excellent thread - many thanks to all.

After some research I bought a Sandisk 16G class 4 card with these results:

16G C4 Sandisk SDSDQM-016G-B35S

(in Sandisk "Mobilemate Duo" USB reader D33D21)

-----------------------------------------------------------------------

CrystalDiskMark 3.0.1 x64 (C) 2007-2010 hiyohiyo

-----------------------------------------------------------------------

* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]

Sequential Read : 18.698 MB/s

Sequential Write : 5.212 MB/s

Random Read 512KB : 18.265 MB/s

Random Write 512KB : 1.372 MB/s

Random Read 4KB (QD=1) : 2.894 MB/s [ 706.5 IOPS]

Random Write 4KB (QD=1) : 1.434 MB/s [ 350.2 IOPS]

Random Read 4KB (QD=32) : 2.849 MB/s [ 695.5 IOPS]

Random Write 4KB (QD=32) : 1.097 MB/s [ 267.8 IOPS]

Test : 50 MB [E: 0.0% (0.0/14.8 GB)] (x5)

Date : 2011/09/19 13:50:58

OS : Windows 7 Home Premium Edition SP1 [6.1 Build 7601] (x64)

Not the greatest, but over 1MB/s is a lot better than the 8G class 6 transcend (8281BB 8G 010S1) card I already had in a phone that only got 0.034MB/s.
[Nook Color General] trevmar:
SanDisk microSDHC from Radio Shack, bought 3 Oct 2011.

Package said: "6 19659 05556 1" - "SDSDQ-016G-A11M" - Class 2

-----------------------------------------------------------------------

CrystalDiskMark 3.0.1 (C) 2007-2010 hiyohiyo

Crystal Dew World : http://crystalmark.info/

-----------------------------------------------------------------------

* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]

Sequential Read : 20.499 MB/s

Sequential Write : 5.226 MB/s

Random Read 512KB : 19.973 MB/s

Random Write 512KB : 1.378 MB/s

Random Read 4KB (QD=1) : 3.495 MB/s [ 853.3 IOPS]

Random Write 4KB (QD=1) : 1.285 MB/s [ 313.8 IOPS]

Random Read 4KB (QD=32) : 3.614 MB/s [ 882.3 IOPS]

Random Write 4KB (QD=32) : 1.029 MB/s [ 251.3 IOPS]

Test : 50 MB [J: 0.0% (0.0/14.8 GB)] (x5)

Date : 2011/10/03 18:17:04

OS : Windows XP Professional SP3 [5.1 Build 2600] (x86)
[Nook Color General] bbogner:
SanDisk SDSDQ-8192 Class 2 8GB from Memory Mogul (via Amazon), bought September 13, 2011

-----------------------------------------------------------------------

CrystalDiskMark 3.0.1 (C) 2007-2010 hiyohiyo

Crystal Dew World :

-----------------------------------------------------------------------

* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]

Sequential Read : 20.723 MB/s

Sequential Write : 8.413 MB/s

Random Read 512KB : 20.117 MB/s

Random Write 512KB : 2.107 MB/s

Random Read 4KB (QD=1) : 3.639 MB/s [ 888.3 IOPS]

Random Write 4KB (QD=1) : 0.025 MB/s [ 6.1 IOPS]

Random Read 4KB (QD=32) : 3.668 MB/s [ 895.5 IOPS]

Random Write 4KB (QD=32) : 0.045 MB/s [ 10.9 IOPS]

Test : 50 MB [I: 0.0% (0.0/7572.0 MB)] (x5)

Date : 2011/10/12 14:12:10

OS : Windows XP Professional SP3 [5.1 Build 2600] (x86)

SanDisk 32G_TF_C4_R7BK Class 4 32GB from Memory Mogul (via Amazon), bought October 10, 2011

-----------------------------------------------------------------------

CrystalDiskMark 3.0.1 (C) 2007-2010 hiyohiyo

Crystal Dew World :

-----------------------------------------------------------------------

* MB/s = 1,000,000 byte/s [SATA/300 = 300,000,000 byte/s]

Sequential Read : 20.731 MB/s

Sequential Write : 6.616 MB/s

Random Read 512KB : 20.139 MB/s

Random Write 512KB : 1.585 MB/s

Random Read 4KB (QD=1) : 2.825 MB/s [ 689.7 IOPS]

Random Write 4KB (QD=1) : 0.611 MB/s [ 149.1 IOPS]

Random Read 4KB (QD=32) : 3.364 MB/s [ 821.3 IOPS]

Random Write 4KB (QD=32) : 0.553 MB/s [ 135.0 IOPS]

Test : 50 MB [I: 0.0% (0.0/29.7 GB)] (x5)

Date : 2011/10/12 14:02:53

OS : Windows XP Professional SP3 [5.1 Build 2600] (x86)
[Nook Color General] av8nsteve:
Hello from yet another noob. Thanks for this thread. I've had my Nook Color since June and have yet to root it.

Last week, I bought a Samsung 32 GB Micro (on ebay - and not here yet) before I found this thread. It WAS to be my boot drive. Since it probably won't score well, I'll use it for data when my NC is not rooted.

This week I bought what was supposed to be a Sandisk Class 2 16GB Micro SD card on Amazon from BoBotechnic (aka TAC Digital Trading Inc and ABX ProTECH). A Class 4 card arrived today instead. It seems to score well:

-----------------------------------------------------------------------

CrystalDiskMark 3.0.1 x64 (C) 2007-2010 hiyohiyo

Crystal Dew World :

-----------------------------------------------------------------------

Random Read 4KB (QD=32) : 3.384 MB/s [ 826.3 IOPS]

Random Write 4KB (QD=32) : 1.362 MB/s [ 332.5 IOPS]

Test : 100 MB [F: 0.0% (0.0/14.8 GB)] (x5)

Date : 2011/10/12 17:04:36

OS : Windows 7 Home Premium Edition SP1 [6.1 Build 7601] (x64)

I hope that this is useful information.
[Nook Color General] jrobinsky:
how did you benchmark your sd cards? I got the program but it only shows my HD. I put my sd card in my card reader in my usb port...any ideas>?
[Nook Color General] bbogner:
You need to have the SD card already in your computer before opening the program. Make sure Windows assigns it a drive letter, then open CrystalDiskMark and it should be in the drop down.